bjects of trial with a view to their domestication, we find ourselves
at once embarrassed by the exceeding wealth of our opportunities. It is
impossible within the limits of this article to treat, even in the
catalogue way, a vast number of forms which commend themselves for
experiment. Something of the richness of the field, however, may be
judged by noting some of the more conspicuous forms, as we shall now
proceed to do. Beginning with the insects, the lowest forms in the
animal series which have proved in any sense domesticable, we note that
wide as is this realm of life it offers but few opportunities such as
the domesticator seeks. Of the million or more species in the group,
only two, the honey-bee and the silkworm, have been won to man's use,
and there is not another wild form which the naturalist can suggest as
likely to prove a valuable captive. The only use which we are probably
to find for these creatures is where, by some form of culture, we may
induce predatory or parasitic species more effectively to do their
destructive work on noxious forms of the class. So well fitted is this
group for purposes of self-defence that however much man may interfere
with the course of nature, he is not likely to sweep any of their
multitudinous kinds from the earth, though experience clearly shows that
by the methods above mentioned they may be greatly reduced.

It is among the vertebrate forms alone that we find animals which by
their characteristics of body or of mind are well fitted to have an
economic or social value. There alone are the qualities of flesh or of
the external covering such as to make them in a high measure valuable,
and the instincts of a nature to fit them for association in man's work.
Even among these back-boned animals we find that the lower groups--the
fishes, the amphibians, and the reptiles--promise little in the way of
gains as compared with the higher groups, the birds and mammals; yet
even among these inferior creatures we find certain forms which give
promise of improvement under the care of man. Some of the fishes readily
learn to come to any one from whom they may expect food, and they
indicate in other ways that they are capable of a certain intellectual
advance. The frogs and toads readily learn to recognize a master.
Several of the larger members of the first-named forms could
advantageously be bred so as to be very useful as food. The common hop
toad of our gardens is an admirable helper